Oil-field jack



FRED m 8103;:

' ATTORNEY Patented July 23, 1929.

UNITEDOSTATES PATENT oar-ICE.

FRED W. STOBK, O1 SAGINAW, MICHIGAN, ASSIGNOR TO STOBK ENGINEERING- COI- IPANY, INCORPORATED, OF S AGINAW, MICHIGAN, A CORPORATION OF MICHIGAN.

' Application filed June 4, 1927. serial 11.. 198,586.

This invention relates to oil field jacks and machines of like character, in which a walking beam is employed to actuate a drill rod, ca 1 e or the like whichmust be made to travel I 5 in a straight line and as nearly .as possible without any sidewise movement.

An object of my invention is to provide on the walking beam a device which while traveling up and down with the beam will constrain the well rod to travel in a straight line, al-

though the. end of the beam trave s in the arc of a circle.

A further object is to avoid wear on the packing box at the top of the well casing and thereby prevent leakage, unnecessary friction and noise.

The means by which I attain these objects is illustrated in the accompanying drawings, in which Fig.1 is a side view, partly broken away, showing the working end of a well jack embodying my invention. 7

Fig. 2 is a top plan view of the pa r of links that constitute the flexing connection of Fi 1, the walking beam removed.

ig. '3 is an end view of the parts shown in F 1. I

Fig. 4 is a horizontal section on line 4-4 of F1 3.

ig. 5 is a sectional view of the cam on line 5 5 of Fig. 1.

As is clearly shown in the drawings, the

" jack structure consists in the usual beam stand 1, the walking beam 2 mounted thereon by means of a walking beam saddle pin 3, and

an arc link, or as shown in Fig. 3, a pair of are links 4, 4 ivotally sus ended from gudgeons 5, 5 on a racket 6 bi urcated to permit the polished plunger rod 7 to pass.

The upper end of link 4 travels in the are of a circle with saddle pin 3 as a center. Heretofore the lower end of the link, connected by means of clamp 8 to plunger rod 7, has been guided only by a suitably packed gland 7" in the well head, and the resulting sidewise pull on the rod caused the wear on the gland and the leakage, noise and undesirable friction which are avoided in machines embodyin the present invention.

The lower part of the are links 4, 4, the

I clamp 8 and plunger rod 7 are constrained to travel in a straight line without any guiding assistance from the gland, or, if for any purpose it is desired to guide the rod in a predetermined line, which need not necessarily be an exactly straight line, it can be done by a curved way slight modification of cam without departing from my invention as herem set forth and claimed. I

The means by which the rod 7 is guided consists primarily of a flexing connection hmged at one end to the beam stand 1 and at the other end to the lower part of the arc link 4:, and a suitable guiding device, such as a or cam 9 fixed to the walking beam, preferably beneath it, as shown in the drawings.

The flexing connection comprises preferably a'pair of links hinged together by a pivot pm 10 which is guided in cam 9. One of the links, 11, is hinged "at one end to the beam stand and the other link, or preferably a pair of links 12, 12 are hinged at one end to the lower part of the arc link 4, and to the clamp 8, asshown in Figs. 1 and 3.-

The dotted lines in Fig. 1 indicate the position of the walking beam and cam at the top of the stroke. The radial distance from the point where link 11 is hinged to stand 1 to the center of clamp 8 when the walking beam is raised is indicated by A, and when the beam is half-way down this radial distance. is shorter, as at A. Still further below the mid.-

structure of a. single dle of the stroke the radial distance again inup and down. The exact path of this curved way or cam 9 depends upon the proportions of the various parts, such as the walking beam, the are link 4 and the links 11 and 12, but the shape of the cam for any given conditions of size and proportion and length of travel can beeasily obtained by means of suitable movable gauges or forms representing the various parts, either full size or to scale. The

. shape and size of cam 9 is obtained by means of a scribing pin representing the center of pin 10, when the center line of clamp 8 is made to travel up and down along a straight ed e which represents the line of travel of t e well rod 7. If desired, the rod can be made to travel at a slight angle from the vertical, or if for any purpose a slight sidewise movement is desired it can be easily obtainedby ing connection comprising a pair of links, a

' pivot pin hinging said links together, one

of said links hinged at one end to the beam stand, the other link hinged at one .end to the lower part of, the arc link, and a cam fixed upon the walkin beam and slidingly engaged by said pin for exing said connection during the up and down movement of said beam to constrain the lower part of the arc. link to travel in a straight line. I I

2. The combination of abeam stand, a walking beam thereon, an arc link pivotally suspended from an end of said beam, a flexing connection comprising a pair of links, a pivot pin hinging said links together, one of said links hinged at one end to the beam stand,

the other link hinged at one end to the lower r part of the arc link, and a curved guide carried by'the walking beam and engaging said pin for flexing said connection to constrain the lower part of the arclink to travel in a straight line.

3. The combination of a beam stand, a walkin beam thereon, an arc link pivotally suspen ed from said beam, a flexing connection comprising a pair of links, a, pivot pin hinging said links together, one of said links hinged at one end to the beam stand, the other link hinged at one end to the lower part of the arc link, and means carried by the walking beam and applied upon the flexing connection intermediate its ends for flexing. it to constrain the lower part of the arc link to travel in a predetermined line.

'4. The combination (if a beam stand, a walkin beam thereon, an arc link pivotally suspen ed from an end of said beam, a fiex-. 1 ing connection hinged at one end to the beam 4 stand and at the other end'to the lower part of the arc link, and means carried by the walking beam and applied upon the flexing con-. nection intermediate its ends for'flexing it to constrain the lower part of the arc link to travel in a predetermined line.

In testimony whereof, I aflix my signature.

FRED W. STORK. 

